I manage a cluster of cPanel shared hosting servers and am considering utilising cPanel DNS only to run two (or more) dedicated DNS servers separate from the hosting servers. I'm hoping this will give me much more flexibility in moving hosting accounts between shared hosting servers.
I'd like some thoughts on a suitable specification for machines running cPanel DNS only.
Understandably what is required of a dedicated DNS server in terms of specs is, to an extent, dependent on the number of DNS records being served from it.
What I'm trying to get an appreciation of is what is required of a cPanel DNS only machine compared to a full cPanel machine.
The DNS only machine doesn't have a mail server, web server, database server and other related non-DNS applications that are present on a regular cPanel server. Therefore compared to what is required of a regular cPanel server, a cPanel DNS only server could be relatively lower powered in terms of CPU and RAM.
I don't have any experience using cPanel DNS only and so am unaware of how demanding, or not, cPanel DNS only is compared to a regular cPanel server. I'm thinking that RAM is much less of a concern but how little is needed, or what a realistic maximum may be, I can't say.
Does anyone have any experience in dealing with cPanel DNS only? How do the specs of your cPanel DNS only machines compare to your regular cPanel machines? Would something as low spec as a small VPS do the trick, or would going fully-dedicated be better and if so why?
Best Answer
I work with a huge cPanel DNSONLY cluster, 4 clustered servers with over 60-80 shared servers connected to them.
DNSONLY has made a lot of progress and is certainly impressive at the moment, I have never had any issues with it, it is plug and play, really. The documentation is very clear, cPanel is a lot more advanced and professional than the cPanel we knew years ago.
The specifications of my DNS servers are 4GB RAM, 300GB Velociraptors, Quad-core Xeons. Also, unlike what you said, RAM is one of the most important things to have on a DNS server because what named will do is cache the requests in the memory therefore requests will be much faster, instead of spinning up the hard drive. You probably don't have to go the 10K RPM HDD way but it's important to focus more on RAM than anything else, right now on my DNS servers, all the RAM is full of cache which is good.
I'd really suggest going a good VPS too because your DNS servers will become your point of failure in this case, and the difference is that if a DNS server stopped before, it would only be the clients on that server, now failure of all your DNS servers = catastrophic complete failure of everything. Don't cheap out on this, it'll bite you back.
There's on need to setup some weird method of rsyncing and having cronjobs, just use cPanel DNSONLY, it's free, it has a nice decent interface, and it just works with no problems.
To finish, put it on good hardware. Stack up on RAM. Don't cheap out, it'll be a large point of failure. Good luck. It took me ~1 day to create DNS servers (4) and then link all 60-80ish servers to them.
Let me know if you have any further questions, having worked with cPanel for the past 8 years, learned quite a few things. :)